And hubert e



Nov. 6, 1928. 1,690,360

c. R. BROWN ET AL PROCESS OF MANUFACTURING STARCH AND GLUCOSE Filed Oct; 51, 1925 STEEP TUBS FIRST DEGERMINATING MILLS FOSS ivflLLS FIRST GERM SEPARATOR- GERMS OFF HERE THE STEP OF -FIRST SEPARATOR SLOP TREATING MATERIALS BE SCREENED HERE BEING PROCESSED TO A wATER- SECOND DEGERMINATING MILLS I-IYOROcHLORIc ACID Fuss BATH MAY BE PRACTISED AT ANY SECOND GERM SEPARATOR -GE.RMS OFF HERE POINT SUBSEQUENT TO STEEPING AND PRIOR. TQ CONVERSION COPPER REELSHULLS OFF HERE INTO GLUCOSE "-$ECOND SEPARATOR SLOP GRIT SHAKERS GRITS OFF HERE HEAVY STARcI-I LIQUOR PORTION OF HEAVY STARCH LIQUOR RETURNED TO SYSTEM PREFERABLY BUHR Mil-L5 TO FIRST GERM SEPARATOR r S HERE COPPER REELS To FEED I-IOuSE -I-IEAvY STARcI-I LIQUOR OFF HERE STARCH LIQUOR SETTLI NG TABLE GLUTEN OFF HERE i R {TO FEED HOUSE TO STARCH CONVERTER FOR GLUCOSE I \L M I 614 5 am 74 processes.

Patented Nov. 6, 19 28.

UNITE STATES" CHARLES 3. BRDWN, or KANSAS GITY, MISSOURI, AND Bosnian: mason, KEQKU K, IOWA,

riioonss or MANUFACTURING STARCH Ann (assess.

Application" filed October 31, 1925. Serial No. 85,949.

Our invention relates to a new and improved process for manufacturing starch, glucose and other substances from cereals, such as corn or other plant tissues containing starch grains. v y

One object of our present invention is to provide an improved, process of the character indicated above Which Will effect theeXpedividea cheapand economical process for'pro curing exceptionally pure end products or by products of the character mentioned with out requiring eXcessiveWa-shing, tabling and handling of the materials during the process of manufacture; such as has been practiced heretofore in order to procure'end products of therequired degree of purity. e

Other ob ects and advantages accruing to our present lnvent-ion will be readrlypercei-ved from the following description to which reference may now be had fora better understanding of the nature, scope'and'characteristic features of our present invention.

We have appended a drawing which is a schematic diagram of one process for manufacturing starch, which process embodies a form of our invention, the diagram mainly.

and excepting the steps which constitute ourinventlon, being representative of a commercial process for securing starch the end product which is eXcept-ionallyfree from iin purities and adapted for the manufacture of glucose. The schematic diagram is 1llustrative of one Well known process for manufacturing starch prior to its conversion into glucose, eX-ceptthatsuch steps 1n the process are added which constitute the lmprovementfof our present invention, but it isto be understood that our lmprovement s not limited to any specific process but is capable of being applied to any of the present commercial For the purposeof describing with'pzirt-icularity our new and improved process, We Will devote the description of our invention to one process for manufacturing starch and glucose from corn. It is to be kept in mind that the apparatus employed in the commercial manufacture of starch and glmose is very massive and large, including steeping vats, settling tanks, grinding mills, draining and screening boxes, pipes, etc-., all of which embody in their construction large quantities of iron. The materials being processed are usually mixed in steeping tubs with a suitable acid-Water bath which exerts a softening effect upon the kernels and, at the same time,

prevents undesirable ferinent-ative changes. This mixture must necessarily come into int-imate contact with the iron that is incorporated in the structure of the steeping tubs which iron, in turn, is dissolved and appears to combine with the materials in such mannor that. iron compounds are-formed which ive'believe are insoluble iron compounds.

hese iron compounds constitute some of the impurities that must be eliminated from the end products in order to render them suitableas commercial products. Heretofore, it has been very diificult to eliminate these impurities and particularly the iron compounds from the end products Without unduly treating the end products and rehandling them by repeated washings and retabling in order to render them sufficiently pure for commerce. If these impurities are present in any substantial degree, and specially the iron con pounds, the cost of eliminating these impurities has been prohibitive because their elimination could only be efiected by additional treatment and processing Whichresulted in increasing greatly the cost of manufacture. The impurities, and particularly the iron compounds, ifpresent to any appreciable dediluted hydrochloric acid or other suitable acid having an avidity comparable to hydrochloric acid, as for example, nitric acid, sulphuric acid, etc., to starch liquor comprising starch gluten and other soluble and in;

soluble substances at any suitable point in the final washing or tabling, or subsequent tothe tabling if the starch is to be converted into glucose. For instance, the step, in our improved process maybe practiced upon the substance or materials produced at the time ofgrinding the grain subsequent to the steep 'ing step, or upon the number 1? tailings or upon the gluten or any other product or byproduct. i I

It is to be understood tl "ttOUl' present invention, which contei'nplates treating the materials with a water-acid bath is to be dis tinguished from the well known use .of acid. for treating starch during the converting period of the 2 ch into glucose, since our invention directed tothe removal of the iinpurities'from the starch prior to ad lilting the starch into the converters and prior to the starch being converted into glucose anu other products. As a consequence, the by-- products resul ing from the conversion of the starch are purified and the converting process rendered more expeditious because the starch is already purified before converting it into glucose andother products.

The step of our improved proccss,'which consists in subjecting the materials'being processed to the action of a water-acid bath is for the purpose of either rendering soluble or easily removable, the iron compounds or otl conipou ds or substances which are present in the starch liquor or other products or byproducts,.or in the ground'corn, so as to eliminate the said impuriti s during the process of manufacture, or before the period.

of conversion when it is intended that the in'ipurities or other objectionable substzmces either-to become soluble or to render thenz. in such a finely divided state as to cause the impurities to pass oil during the washing of the starch iquor or the washing of the products or byproducts.

' t will be pointed out hereinafter that the step of our invention which contemplatesthe treating of the starch liquor or other products or bfl-iroducts with a water hulrochloric acid bath or other suitable waterac bath may be made at any suitable point in the process of manufacture of the starch audoizr through the battery of the steep tubs.

T rab o to tubs, dissolves the iron which, on coming 1n present invention comprehends r scope the practicing of this purif 3 subsequent to .the steepi of the core-a preferably prior to the tubing step if the final end product is starch; other rise, the this end product is glucose and similar products,

the purifying; step of our invention may be practiced subsequent .to the ta 11g of the starch but prior to the conve V starch into glucose;

As a, specific illustrative example of a preferred method of pl'flCtI-Cllljl' our lilVQlltlOl'l,

we will describe the process of n'i'anufacturing' starch which is diagrammed on the'drawing forming a part of this speci hcation.

The Whole corn is put into the steep tubs which may hold several thousandbushels and.

trap; of the wherein the whole corn kernels are soaked i from 50 to 60 hours in a'warm water bath'contaming from .2 per centto .3 per .centof air '7 d It is usual to'constructf the steep tubs in bat cries, each steep tub bemg 1 0 phurous acid.

to 12 feet in depth and 6 to 8 feet in diameter.

When the steep tubs are'arranged in such a battery formation, thenew corn is admitted into the first steep tub and thesteeping water containing the sulphurous aeidis circulated from tub to tub by'a counter current system which causes the steeping water toflow opposite to the direction of movement ,of'the corn consequence, the dry corn kernels contained in thefirststeep tub are soaked with the oldest steep waterin the battery This steeping Water containing the sulphurous acid ismaintained at a temperature of from 115 F. to 7 180 F by injecting steam, into thesteeping water bath.

As a result of the counter current circulation of the steep water, the corn 1n the first steep tub,wl iich is the new corn, is subjected to a water both that contains ap-' proximately .03 per cent of sulphurous acid while the corn in thelast steep tub of the battery is subjected to the steeping water posse-ssing thefullacidconcentration of substanti- Asa" lie,

ally .2 per cent to .3 per cent of sulphurous acid. The sulphurous acidlseems'to have a softening effect on the glutinous parts of the 7 whole corn kernels and, atthe same time, prevents undesirable fei 'iueutative changes in the corn grains.

The aforementioned steeping water-acid bath, by reason of its coming into contact Wit-ll the iron embodied mthe structure of the steep contact with the phosphates in the new corn combines to form what we believe are insoluble iron phosphates, which are the impurities that must subsequently be eliminated or mini mized to avoid contaminating the starch or other end products or by-products. These insoluble iron phosphate compounds which, on passing forward 1n the process, result 111 the productionof undesirable'and uncomm'er cial end products. Therefore, our invention is directed particularly to the removal of these insoluble iron phosphates in order that the end products such as the starch, the glucose, gluten, number 1'? tailings, etc. will be substantially purified and thereby made commercialf After the whole corn kernels-have been is desirable to separatethe germs from the other parts of the kernels and, therefore, from the Fuss mill'the cracked kernels are passed to the firstgerm separator. Here it is usual to mix the cracked kernels, the loosened germs, the hulls, fibrous material, etc. with heavy starch'diquor that is withdrawn from the system and recirculated in order to carry the bulk of the germs ofi" at the top of the first germ separator. v

The germ separator is a tank containing an agitator so constructed that its movementbringsthe germs to the surface where th-ey'are removed from the separators an appropriately placed opening, the heavier parts of the corn kernelsand the hulls passing off at the o i I reelsas ted to the number 17 silk reels,'as mentioned above. Thematerial left on these bottom of the germ separator, The material coming out at the bottom of the first germ .separatoris called the first separator slop. The first separator slopmay, if desired, be screened to remove the starch therefrom and the residue may t-henl e runint-o a second Fuss .or degerminating mill,"or, if desired, the

WllOl-Of the first separator slopmay be run into the second degerminating mill. Atthe secondgerminating mill the residue is subjected to further grinding in order to make a more complete separation of the germ trom'therest of the kernel. Frointhe second deger-minating mill the material is'passed to a. second gernrseparator, where substantially all of the remaining germs are segregated from the remainingportions of the kernels. The germs from the first and second germ separators are washed by passing them over reels and shakers toremove the starch adhering to them. The

germs are then dried, ground and the oil contained in them 1s pressed out by means of an oil press otthe usual construction. The oil is used principally for soap making and for other industrial purposes. The residue con-v 'stitutesoil cakewhlch is an excellent cattle food and may be ground into a meal or utilized in the original cake. The niaterial'fiowingout of'the bottom of the'second separator, which is now designated as second separator slop, contains the bulk of the starch and this is first run over copperrecls toremove the coarse material, such as the hulls. The material passing through the copper reels, which constitutes starch liquor containing fine grits, small pieces of hulls, etc., is then run over silk shakers or grit shakers. The material passing through the'grit shakers is known as heavy starch liquor and this heavy starch liquor is mainly conducted'to the settling table, while a portion of it is returned into the system, preferably at the first germ separa- 1101' as explained above.

The hulls that are derived from the copper rIels and the grits which are derived from the silk or grit shakers are mixed together and passed to a buhrstone mill where they are reground. The material ted to the buhrstone mill is a damp mushy conglomerate.

From the buhr-stone mill the semi-liquid coarse sawdust inaterialiis led to the feed house where it may be mixed With other byproducts.

The starch liquor passing from thecopper silk reels is called N o. 17 tailings, this be cause it is incapable of passing through the number 17 silk utilized in the construction of these silk reels. The starch liquor passing through the number 17 silk reels is combined 7 with the aforementioned starch liquor passing through the grit shaker and together these two starch liquors are run onto the settling table which will be described later.

The number 17 tailings contain 20% to ion starch and these number 17 tailings are filter-pressed inorder to remove the moisture and are then passed to the feed house where they become part of the feed.

The starch liquor flowing to the settling table has a gravity of about 6 Be. and the temperature of the starch liquor at this time is approximately between'85 F. and 90 F. The settling table is inclined about 4 inches in 120 feet of length and is approximately 24: inches wide. The starch liquor is run onto the table at the rate of 2 gallons to 3 gallons per minute, the starch being heaviest will settle onthe table and the gluten will flow off at the end of the tablev with the table has a specific gravity of about 1' lit) 7 It settled in gluten settlers and the sloppy mass is taken from the'bottom, filter-pressed and then passed to feedhouse' The gluten liquor from the settling table contains a considerable starch content which is difficult to recover as commercial starchf The starch depositedupon the table forms a, substantially thick layer at the upper end of the table and this layertapers oft towards uct, namely, the starch upon the settling table and the only method heretoforeavailable for removing these impurities consisted in subjecting the starch to repeated washings and retabling in order to purify sutficiently the starch for-commercial use. As we have stated above, it is highly desirable to remove these iron compounds and impurities from the starch depositedupon the/table prior to. the time of converting this starch int-o glucose and other end products,

otherwise these end products, such as the glucose, rvill be uncommereial. The procedure heretofore necessary to remove these iron compounds and impurities from the end products has reatly added to the expflenseof manufacturingstarch and glucose, even under-favorable conditions, and, here'- to'rore, it has never been possible to remove vertingof the starch. The difiiculty in purifying the starch, prior to converting t when glucose is the-final end product, has always been. a very serious problem in the manufacture ofglucose, but by practicing the step of our invention, the impurities and particularly What e believe to be the insoluble iron phosphates and compounds are substantially completely removed from the end product prior tothe converting of the starch into glucose and, as a consequence, We. are ableto manufacture glucose very economically and to procure a glucose that extremely pure and subst-an ally devoid of anv insoluble iron co mpciincsi By re'terringagain to the diagram, it has been pointed out that the insoluble iron compouagids are almost completely formed during the timethat the Whole corn kernels are mixed with the sulphurous acid bath in the steeping tubs. From the time that the corn kernels leave the steeping tubs all of and compounds.

starch deposited upon the sett H tion that the ttiflrwatfil bath exerts completely these impurities pllOl to, the con,-

the system. lit

a Watmews? the products and byproducts are centami-a natecl with these insoluble iron phosph s i r e -a e. ge es derived fromthe gel-in s ep, tors. V contaminated with these insoluble hot), (2 p,ounds, the slop dischargeclftrom the. copper reels subsequent to, the treatment of, the 111 terial in the buhr mills. may be contaminated with; these i'mpuritiesfi l? ltunber 1] ta]; ings from the number lisilk'reels may be likewise contaminated, the gluten p1-'O ,cth;e d fro nthe settling tablt may be contaminated withthese impuiities similarly, the

" 1g ta l ts well as the gluten tailing-s n so Qurinvention comprehends the step the aforesaid process which; will purity the y ous materials in order to eliminate substantially from them. hat rye believe tOlbQ- the insoluble iron phosph'atesand compounds and 85 other impurities y As an illustrative example of how our vention may be practiced, the starch taken from the settling table and prior to converted into glucose and otherend prod note is treated with a Water-acid bath, preterably comprising a weak solution of hydro.- chloric acid. The hydrochloric acid, in this treating .bath may "vary in concentration from 02% to 075% and,rin some instances,- my be of h gher onceu it iou' when. the im ur ies are eX Q$ V but he c mes-hie tion oi the acid should-be at all times sufficen ly lo o pr clii e 'a-ny substenta hydr ly i of th s arc y eases t prev n d l ious acti th ron con tajiners or other iron portions of the apparatus, and f uc l w 3 c n en ra ijen that the rate of solution of any iron may in con -a t with, he c l-ua e bat l will he Sub" stantially negligible with respect to the aet c on the impurities to, be removed thereby. 'Vllhfln the starchfroin the settling table is washed with; this hydrochloric acidjba-th, the insoluble r Ph sphates and o h r i em, impur ties are readily removed from th" starch. t i u the ry that hi iy l u il ,c-jacid l lll bath increases the" colloidal dispersion of these insoluble iron compound, 1m impurities which are readily war the materal bein processed and run fr l v he that this hydroc lor' acid bath renders the a-hu'esa-id impi i s soluble but,at any rate, we have i'oun that l? whcn'proceeding with the process for manuiiaqturing starch, glucoseand other by prodacts and end products, suhetantially pure by: products and. end products maybe'secured by washing the materials being processed a t-any a vpfropriate point in the 'process iv-ith' vu'dre hl i a i l ba h a ru heaetc-r described thereby iacilitating thefremoval of the impurities; This to lie-understood, of e egram the Stepotour .invention thatcomprises washing the materials being. processed with this hydrochloric acid process after the whole corn kernels leave bath may be practiced at any point in the the steeping tubs. For instance, the germs drawn from the germ separators may be washed with this hydrochloric acid bath in order to cleanse them of the insoluble iron 7 phosphate compounds. Again, the number 17 tailings may be washed with this hydrochloric acid bath in order toeliminate therejil'OllltllG insoluble iron phosphate compounds and other impurities Thegluten flowing from the scttlii'ig table may be also treated with this hydrochloric acid bath in order to remove the impurities and, likewise, the starch deposited upoiithe settling table may be ti'cated with this hydrochloric acid bath prior to converting it into glucose.

If the materials being processed are to betreated w th the water-hydrochlonc acid bat-h previous to the tabling of the starch, the

' bulko'i the impurities which have been made soluble by this acid bath or which have'had their c olloidal dispersion increased by reason thereof are carried off in the gluten water and in the water which is pressed from the vnumber '17 tailings. The resulting starch and lay-products under such treatment'will be'pure enough for ordinary manufacturing purposes.

' Ilfthe variousbyproducts are to be treated il separately by subjecting. them to a waterhydrochloric acid bath,the procedure may be carried on as -follows: in treating the number 17 taili gs they are mixed after they leave the reels with 'a water-liydrochloric acid bath to ake the impurities contained therein either soluble or possessed o'L increased colloidal dispersion. The mass is then run into a filter press fitted with. standard washing devices, Such a filter press is well known in thea-rt and inanysuch presses of standard construction will be suitable.

Here the impurities'are washed from the number 17 ta1lings by passing water through the filter cake until such impurities are reduced to a minin'iuin. v V V If the gluten is to be treated with a waterhydrochloric acid bath, the settled gluten from thegluten settlers may be treatedin the sameman'ner as the number 17 tailings. If the starch is to be treated w th the water-hydrochloric acid bath, it is flushed from the settling table with water and to the resulting liquid starch bath hydrochloric acid addedand the whole is then filtered in a plate and at'rame washing press or any standard construction, or on continuous filter of any of the well known forms which are fitted with washing sprays. In washing any of the-by-products, hydrochloric acid may or may not be added, as desired, to the washing water which may be applied to the various end products when such end products are in the form of cakes, resulting from the passng of the materials through the various I While we have indicated in theldiagrainmatic representation a. process for manufacturing starch from whole corn'kernels which process includes the step of our invention which is directed to the treating of the material being processed with a water-hydrochloric acid bath, it isto be understood that our invention may be practiced at any point in the process subsequent to the time that the naterial being processed leaves the steeping tubs and prior to the time that the starchis 1 to be converted into glucose. For instance,

the materials beingprocessed may be treated in accordance with our invention with the hydrochloric acidbath before or during the steps of washing, tabling or settling thereby rendering the impurities readily removable to produce substantially pure end products.

It is our theory that the acid water, namely thesulphurous acid water, when mixed with the whole corn kernels as they are first fed into the steep ,tubs dissolves the iron embodied in the structure of the tubs and that this dissolved iron, on coming in cont-act with the phosphates.contained'in the whole corn kernels combines to form insoluble compounds which appear to be insoluble iron phosphates. Heretofore these impurities have been very diflicult' to remove and. the

methods practiced for removing them con 1 sisted generally in repeated washing and retabling.v As a consequence, these oldmethods for eliminating the impurities have been expensive and tedious and the end products suitable for converting into starch have been a'small percentage only of the total quantity of starch present therein. By means of our invention being practiced during the process of i'nanufacturing the starch, these iron impurities are capable oi being substantially completely removed with a. very economical treatment, namely, subjecting the material beingprocessed, at any suitable point, to a \vater-l'iydrochloric acid bath of the proper concentration, as herein described. lhe hydrochloric acid bath removes the iron in purities undoubtedly by increasing their col- .loidal dispersion. Consequently, the 1m prities are capable of being readily washed from the materials being processed and substan'tially pure end products are the result.

"It is to be understood, of course, that our invention is directed'to an improved process of manufacturing starch and glucose from with the ipon qr othei impurities foiiri'diin "thihatefial being proc'es'seclio'r tor mre'aslng 2.1 lniri'fying the materials beiiig jprp'cesscl,""as

SO'lLlblll Zed iron 's'a'ltsarid th residual aid.

' telials "containing the same which '(ioniprises 7 phosphates ancl iliisidiialhalpgen acidj v The fpr'icess fo'r l' emoving substantially insdliible'iroii phosphates from stai'hyi'naterials 'c on't ai'h'ing the" same w'hiich Comprises ilisoliible iio'n phosphates-are 'soliibilized, and

colloidal 'disprsiOn (if these i iihpui'ities Ch a M nner that they "maybe readily comprises -siibjeting saiclstarchy 1 materials rials.

wherein fai'inae'ous materials are siihj'e ctecl to steeping ina sulphi'iro'us acid"ba thwv hsrehy in'soliible iron salts are introduced" into said 53 In the pi'ocss ofhianiifactiiring starch phosphates from" starch -ina'trials-whih' materials; that'step which cbmpri'ses gtr'eating sai cln1aterialssubseqilnt'tb the steeping with a dilute hydrochloric adicl {solution ther'by *ausingsai cl' salts in said matfia'ls ftd be inore completely collo'i'clally dispersed; and

toT prccliicleany substantial"hydrolyz 1 HU BERT E. NELSQN. 

